ron@d7577 ~/.mame $ gdb mame
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Reading symbols from mame...
done.
(gdb) 
(gdb) r coco3 -flop1 ../Downloads/TEST.DSK
Starting program: /usr/local/bin/mame coco3 -flop1 ../Downloads/TEST.DSK
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7fffe621f700 (LWP 28654)]
[New Thread 0x7fffe996d700 (LWP 28655)]
[New Thread 0x7fffd69f7700 (LWP 28656)]

Thread 1 "mame" received signal SIGSEGV, Segmentation fault.
0x0000000007e3411a in devcb_write<int, 1u>::operator()(address_space&, unsigned int, int, unsigned int) ()
(gdb) backtrace
#0  0x0000000007e3411a in devcb_write<int, 1u>::operator()(address_space&, unsigned int, int, unsigned int) ()
#1  0x00000000074e58ca in wd_fdc_device_base::ready_callback(floppy_image_device*, int) ()
#2  0x000000000703bd30 in floppy_image_device::set_ready(bool) [clone .part.122] ()
#3  0x0000000007040fa2 in floppy_image_device::index_resync() ()
#4  0x0000000008b405fa in device_scheduler::timeslice() ()
#5  0x0000000008aee118 in running_machine::run(bool) ()
#6  0x000000000588b9f2 in mame_machine_manager::execute() ()
#7  0x0000000005916fe6 in cli_frontend::start_execution(mame_machine_manager*, std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > const&) ()
#8  0x000000000591721e in cli_frontend::execute(std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > >&) ()
#9  0x0000000005889b71 in emulator_info::start_frontend(emu_options&, osd_interface&, std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > >&) ()
#10 0x0000000001c830cf in main ()
(gdb) 
